1. Field of the Invention
The present invention relates to a semiconductor device and a method of manufacturing a semiconductor device.
2. Description of Related Art
In a semiconductor device that controls ON/OFF of current, when the current flows in a semiconductor substrate, a temperature thereof is increased by heat generation. The generated heat is hardly radiated from a central part of the semiconductor substrate when compared to a peripheral part of the semiconductor substrate, and thus the temperature is easily increased. In the semiconductor device disclosed in Japanese Patent Application Publication No. 2007-027440 (JP 2007-027440 A), an interval of operation cells in the central part of the semiconductor substrate is increased. Accordingly, a density of the operation cells formed in the central part is set to be lower than a density of the operation cells formed in the peripheral part of the semiconductor substrate. Therefore, a heat value per unit area of the central part in the semiconductor substrate is suppressed, and temperature distribution in the semiconductor substrate becomes uniform.
However, in a technique disclosed in JP 2007-027440 A, if the interval of the operation cells in the central part is increased without reducing the number of the operation cells formed in the semiconductor substrate, a physical size of the semiconductor substrate is increased.